Regular expression for single state FA without final state

Question

Give the language and Regular Expression for this finite automaton.

Is it a DFA or NFA? Can we draw a DFA without a single final state?

Answer 1

This is a $DFA$. We are allowed to make the set of final states F in the definition of $DFA$ as empty. this will be equivalent to the complement of $DFA$ which accepts $Σ^*$ . This $DFA$ doesn't accept any input.

Answer 2

RE  for this  DFA  is   { }

i.e   phy

very simple